Turbo Grafx/PC engine CD Gear replacement available! $12 shipped

[Keith Courage]

Okay, guys, I finally got my shipment of gears in the mail. Just so you know these gears are not direct OEM replacements. The gears I have are to change the gear setup slightly to make it a 2 gear solution instead of 3 gears. So there is more work to be done besides just replacing one gear. The downfall of the two gear solution is that the drive is a bit noisier. However, on the plus side the load times for games are cut almost in half I am charging $12 for these gears since I have to drill out the holes on them to the correct size which requires some patience. If you go too fast the hole gets crooked rendering the gear useless. I test out every gear to make sure it is nice and straight before shipping.
 

Pics of another thread on here will be used to explain some of this since I don't currently have a drive apart that I can take pictures of. I will update with current pics of everything once I perform this repair myself again in the future.
I am going to start my write up on this as if everyone here already knows how to take their drive apart and disconnect the ribbon cables for the CD lens. That part is found in this write up  https://www.pcenginefx.com/forums/index.php?topic=7193.0


1. First you have to get the motherboard moved out of the way so you can see the lens drive assembly. Once at that point you will want to unscrew the 3 screws(circled in red) holding down the lens assembly and very carefully lift the assembly up. Do not lift too far cause there will still be wires attached to it.



2. Now that you have the lens assembly up in the air you are going to have to remove the middle Metal shaft for the old broken middle gear(cirlced in red). You do this by using a pair of small pliers and pull out while twisting it back and forth. The metal shaft I speak of is the one that is stationary and doesn't spin.


3. Remove the small metal part below the lens motor(circled in red). This is to make enough room for our new gear to fit. You do this by removing the one Phillips screw that is holding it on. After that part is off put the screw back in so your lens motor is still held on well.


4. Remove the old gear from the lens motor by just pulling it off. It may be on there pretty good so use a small flat head screw driver to push it off if you have to. Now push on the new gear until the teeth line up nicely. The new gear will take a bit of force to push it on. If you push it on too far use a flat head screw driver to pry it back off again.






5.(optional and usually not needed)If the gear seems like it is too far away from the main spindle you might have to flip over the lens motor. Not sure why if it's due to the mounting or if the center spindle on the motor isn't perfectly straight but I'd say about %10 of CD drives have to have the lens motor flipped over for the gear to line up correctly.


6. You must change the polarity on the lens motor itself. To do this you start by pulling the white connector end for it off of the motherboard(circled in red). It is the cable with a blue and pink wire. Once you have the cable disconnected from the board you use a very small flat head to hold the plastic clips away on the white connector end. With the plastic clips held out you can pull out the two wires. Now that the wires are removed just put them back in the opposite direction. The wires should clip back in. Alternatively you could de-solder and then re-solder the wires in reverse on the motor itself. When you have it correct the wires will be opposite of the wires in the picture here. So blue on the right and pink on the left instead.


7. re-assemble your drive by putting the lens assembly back and re-attaching your lens ribbon cables. Put the bottom cover back on your drive but do not screw the bottom panel back on yet as you might need to remove it to do some adjustments.

8. Your drive should now be usable but there may be some fine tuning to be done. Most likely you won't have to do this next step but 10% of the time the drive will need the spindle speed potentiometer adjusted a little to make up for the slightly different gear size(circled in red). The best way to test this is to use an audio CD with lots of tracks on it. Hit the play button on your CD drive and listen to the first couple tracks and see if they work fine. Then try playing the very last tracks on the CD and see if they also work fine. If not then you will have to adjust the speed slightly one way or the other. The last tracks on a CD might skip a little until you get it right. I use YS 1&2 to test this out since it has the most audio tracks of any game I can think of. This part is what can take a quite a bit of time to get it just right.

[BlueBMW]

Two words... 

[Game-Tech.US]

Don't suppose you want to share info on how we can do it ourselves cheaper?
For instance where does the gear you're using come from, how many teeth, O.D., what size is the hole we need to drill the gear out to, etc.
I just can't justify spending $15 on ONE gear.

[Trevpwnsnoobs]

I approve

[Keith Courage]

I am sorry to say but the gears are close to $10 each if you buy them one at a time and not in bulk. The said gear comes in a package of about 10 other different gears(not usable) which is why it is $10. I have not been able to find the gear on it's own to make things cheaper. Also, the drill bits are on ebay which is the cheapest I can find for $2.64 a piece with the shipping so you are almost at $15 anyways. The drill bit is a micro bit size 54. You cannot get the drill bits in a hardware store. I never bothered measuring the gear before. I suppose I can try to measure it. I just randomly ordered a bunch of gears from places until I found the right one. It took me quite a bit of trial and error till I found the right match.  

[BlueBMW]

$15 is a very fair price for replacement gears.  This is a known fix for dirt cheap.

Thanks kieth for offering these!

[thesteve]

that ends up a bit cheaper than my pulleys, and i dont know how it compares to chops gears.

[Charlie]

$15 is an excellent price for this.  I priced a bulk custom-made gear set for the CD drive, the best price I could get was $18 in bulk of 500 pieces.  Throw in package/shipping, and I would have charged at least $25 just to break even.  I cannot see any reason why anyone would not pay $15 and do the fix yourself.  I have done a number of gear replacements on these drives, and the effort is minimal. 

The other option was to do as Steve did,.. buy a "compilation" set of gears, find which one gear in which package of many gears would actually be usable, and proceed to buy multiples of that package.  (And gain lot's of excess gears in the process)

Good job, Steve!!

Charlie
 

[grahf]

Awesome! $15 is more than fair.

[Platinumfungi]

Bravo   

[SignOfZeta]

Don't suppose you want to share info on how we can do it ourselves cheaper?
For instance where does the gear you're using come from, how many teeth, O.D., what size is the hole we need to drill the gear out to, etc.
I just can't justify spending $15 on ONE gear.

Obviously you haven't been tracking this problem as long as some other people here. Its worth at least four times that since it turns a totally useless paperweight back into a usable drive.

I will buy one of these for my spare (broken) drive but I'm not to excited about replacing it right away. The idea of "adjustment" of a drive makes me sick to my stomach. I'm trying to tweak a FC disc drive right now and its basically torture.

[Game-Tech.US]

Don't suppose you want to share info on how we can do it ourselves cheaper?
For instance where does the gear you're using come from, how many teeth, O.D., what size is the hole we need to drill the gear out to, etc.
I just can't justify spending $15 on ONE gear.

Obviously you haven't been tracking this problem as long as some other people here. Its worth at least four times that since it turns a totally useless paperweight back into a usable drive.

Obviously not true, April of 2008 I posted a 'how to' on diagnosing and fixing the return to center limit switch in the tgcd.
That was right after forum members really started investigating this gear issue.

To me its too much, but that may have a lot to do with how many units I need to fix, 15+.
If I only had one or two then it may not seem that excessive...
If we knew what this gear's OD and tooth count were, we could possibly order it in bulk for cheap.
Should be cheaper since its not an obscure reduction gear, just a simple spur gear.

Also, thought i'd much rather have a drop in replacement, a gear on gear solution interests me more than any belt type fix. That's a whole other set of problems.

Also, the drill bits are on ebay which is the cheapest I can find for $2.64 a piece with the shipping so you are almost at $15 anyways. The drill bit is a micro bit size 54. You cannot get the drill bits in a hardware store.

Grainger has them for $1.10 a piece.

there may be some fine tuning to be done. 75% of the time drives will need the spindle speed potentiometer adjusted a little to make up for the slightly different gear size(circled in red).

I was wondering, if the motor and worm gear spindles are the same diam. you could put your new big gear on the worm gear shaft and the smaller gear off the worm onto the motor shaft and maybe it would run a little slower and maybe less noise or possibly less adjustment???

[BlueBMW]

To me its too much, but that may have a lot to do with how many units I need to fix, 15+.
If I only had one or two then it may not seem that excessive...
If we knew what this gear's OD and tooth count were, we could possibly order it in bulk for cheap.
Should be cheaper since its not an obscure reduction gear, just a simple spur gear.

For someone wanting to fix their ONE CD unit for personal gaming use, $15 is fantastic as it saves someone from having to spend $70 to $90 for a working CDROM.  For someone with 15+ units... $15 each is high because what else would someone do with 15+ units but sell them once they were working?  Every bit of cost put into each drive makes them less profitable.

Also, thought i'd much rather have a drop in replacement, a gear on gear solution interests me more than any belt type fix. That's a whole other set of problems.

Not really... infact, the belt drive has a few things that all these substitute gear solutions dont have.  First of all you dont need to reverse the motor, secondly its silent.  I can understand that belts wear out, but lets be honest, how long do they typically last?  And say it does wear out... they're less than a $1 and might take you 10 minutes to replace.

I was wondering, if the motor and worm gear spindles are the same diam. you could put your new big gear on the worm gear shaft and the smaller gear off the worm onto the motor shaft and maybe it would run a little slower and maybe less noise or possibly less adjustment???

The worm gear and motor have vastly different diameters.  The worm gear is basically a 1/8" press fit while the motor is MUCH smaller.

In justification of the price, I'll throw out a comparison....

The region mod chips I had made up...  I've been asking $18 each shipped for them which is about what I've seen similar region mod chips sell for in the past.  Each chip has to be soldered, packaged, labeled and shipped.  I go even further and I test all the connections with a meter to make sure there are no missed / poor solder connections.   The cost of the parts is around $3 each, but when you add in the cost of supplies, shipping mailers, shipping, time / effort to package / mail them.... the profit is under $10 each.  Not to mention I had put in about $500 up front to make them in the first place.  Before that, there was a lot of time spent developing the design / method of the chip.  So the $8 or $9 profit I make pays me for the time / effort I put into making / shipping them, AND for the development time before the chips were made.  Additionally... when one fails, I'll back it up and replace any defective ones for free.  Inevitably it will happen and I have to plan for that eventuality.

Similarly, Keith Courage had to locate gears that worked pretty much by trial and error.  I've tried too, and believe me its frustrating to have 50 or so gears that you've bought and paid for that dont work!  So in the end, even if Keith is making $10 profit on each gear... good for him.  That's well on par with the industry for this sort of repair part.  Like me he has to spend time drilling / preparing / checking the gears and then packaging and shipping them.

end rant

[chop5]

very nice chris,excellant tutorial.
come on over to the shoutbox were we techys talk for hours on end of the obscure technologies of mankinds past and how to restore them 

[Game-Tech.US]

To me its too much, but that may have a lot to do with how many units I need to fix, 15+.
If I only had one or two then it may not seem that excessive...
If we knew what this gear's OD and tooth count were, we could possibly order it in bulk for cheap.
Should be cheaper since its not an obscure reduction gear, just a simple spur gear.

For someone wanting to fix their ONE CD unit for personal gaming use, $15 is fantastic as it saves someone from having to spend $70 to $90 for a working CDROM.  For someone with 15+ units... $15 each is high because what else would someone do with 15+ units but sell them once they were working?  Every bit of cost put into each drive makes them less profitable.

Yes, that's what i'm doing, buy em, fix/mod em, resell em, hope for some profit.

Also, thought i'd much rather have a drop in replacement, a gear on gear solution interests me more than any belt type fix. That's a whole other set of problems.

Not really... infact, the belt drive has a few things that all these substitute gear solutions dont have.  First of all you dont need to reverse the motor, secondly its silent.  I can understand that belts wear out, but lets be honest, how long do they typically last?  And say it does wear out... they're less than a $1 and might take you 10 minutes to replace.

Yes, but a drop in would take less time and effort to fix each unit and work as intended. My other concern about the belt is it would slip when the sled reaches either end and thats not how it was made to work. It may work perfect and I do like the idea of being a silent operation, but would still rather have an original replacement.

I was wondering, if the motor and worm gear spindles are the same diam. you could put your new big gear on the worm gear shaft and the smaller gear off the worm onto the motor shaft and maybe it would run a little slower and maybe less noise or possibly less adjustment???

The worm gear and motor have vastly different diameters.  The worm gear is basically a 1/8" press fit while the motor is MUCH smaller.

I see, been too long since i've had one open and couldn't tell from the pics, too bad...